Documentation/git-pack-objects.txt

   1 git-pack-objects(1)
   2 ===================
   3
   4 NAME
   5 ----
   6 git-pack-objects - Create a packed archive of objects
   7
   8
   9 SYNOPSIS
  10 --------
  11 [verse]
  12 'git-pack-objects' [-q] [--no-reuse-delta] [--delta-base-offset] [--non-empty]
  13         [--local] [--incremental] [--window=N] [--depth=N] [--all-progress]
  14         [--revs [--unpacked | --all]*] [--stdout | base-name] < object-list
  15
  16
  17 DESCRIPTION
  18 -----------
  19 Reads list of objects from the standard input, and writes a packed
  20 archive with specified base-name, or to the standard output.
  21
  22 A packed archive is an efficient way to transfer set of objects
  23 between two repositories, and also is an archival format which
  24 is efficient to access.  The packed archive format (.pack) is
  25 designed to be unpackable without having anything else, but for
  26 random access, accompanied with the pack index file (.idx).
  27
  28 Placing both in the pack/ subdirectory of $GIT_OBJECT_DIRECTORY (or
  29 any of the directories on $GIT_ALTERNATE_OBJECT_DIRECTORIES)
  30 enables git to read from such an archive.
  31
  32 'git-unpack-objects' command can read the packed archive and
  33 expand the objects contained in the pack into "one-file
  34 one-object" format; this is typically done by the smart-pull
  35 commands when a pack is created on-the-fly for efficient network
  36 transport by their peers.
  37
  38 In a packed archive, an object is either stored as a compressed
  39 whole, or as a difference from some other object.  The latter is
  40 often called a delta.
  41
  42
  43 OPTIONS
  44 -------
  45 base-name::
  46         Write into a pair of files (.pack and .idx), using
  47         <base-name> to determine the name of the created file.
  48         When this option is used, the two files are written in
  49         <base-name>-<SHA1>.{pack,idx} files.  <SHA1> is a hash
  50         of the sorted object names to make the resulting filename
  51         based on the pack content, and written to the standard
  52         output of the command.
  53
  54 --stdout::
  55         Write the pack contents (what would have been written to
  56         .pack file) out to the standard output.
  57
  58 --revs::
  59         Read the revision arguments from the standard input, instead of
  60         individual object names.  The revision arguments are processed
  61         the same way as linkgit:git-rev-list[1] with `--objects` flag
  62         uses its `commit` arguments to build the list of objects it
  63         outputs.  The objects on the resulting list are packed.
  64
  65 --unpacked::
  66         This implies `--revs`.  When processing the list of
  67         revision arguments read from the standard input, limit
  68         the objects packed to those that are not already packed.
  69
  70 --all::
  71         This implies `--revs`.  In addition to the list of
  72         revision arguments read from the standard input, pretend
  73         as if all refs under `$GIT_DIR/refs` are specified to be
  74         included.
  75
  76 --window=[N], --depth=[N]::
  77         These two options affect how the objects contained in
  78         the pack are stored using delta compression.  The
  79         objects are first internally sorted by type, size and
  80         optionally names and compared against the other objects
  81         within --window to see if using delta compression saves
  82         space.  --depth limits the maximum delta depth; making
  83         it too deep affects the performance on the unpacker
  84         side, because delta data needs to be applied that many
  85         times to get to the necessary object.
  86         The default value for --window is 10 and --depth is 50.
  87
  88 --window-memory=[N]::
  89         This option provides an additional limit on top of `--window`;
  90         the window size will dynamically scale down so as to not take
  91         up more than N bytes in memory.  This is useful in
  92         repositories with a mix of large and small objects to not run
  93         out of memory with a large window, but still be able to take
  94         advantage of the large window for the smaller objects.  The
  95         size can be suffixed with "k", "m", or "g".
  96         `--window-memory=0` makes memory usage unlimited, which is the
  97         default.
  98
  99 --max-pack-size=<n>::
 100         Maximum size of each output packfile, expressed in MiB.
 101         If specified,  multiple packfiles may be created.
 102         The default is unlimited, unless the config variable
 103         `pack.packSizeLimit` is set.
 104
 105 --incremental::
 106         This flag causes an object already in a pack ignored
 107         even if it appears in the standard input.
 108
 109 --local::
 110         This flag is similar to `--incremental`; instead of
 111         ignoring all packed objects, it only ignores objects
 112         that are packed and not in the local object store
 113         (i.e. borrowed from an alternate).
 114
 115 --non-empty::
 116         Only create a packed archive if it would contain at
 117         least one object.
 118
 119 --progress::
 120         Progress status is reported on the standard error stream
 121         by default when it is attached to a terminal, unless -q
 122         is specified. This flag forces progress status even if
 123         the standard error stream is not directed to a terminal.
 124
 125 --all-progress::
 126         When --stdout is specified then progress report is
 127         displayed during the object count and deltification phases
 128         but inhibited during the write-out phase. The reason is
 129         that in some cases the output stream is directly linked
 130         to another command which may wish to display progress
 131         status of its own as it processes incoming pack data.
 132         This flag is like --progress except that it forces progress
 133         report for the write-out phase as well even if --stdout is
 134         used.
 135
 136 -q::
 137         This flag makes the command not to report its progress
 138         on the standard error stream.
 139
 140 --no-reuse-delta::
 141         When creating a packed archive in a repository that
 142         has existing packs, the command reuses existing deltas.
 143         This sometimes results in a slightly suboptimal pack.
 144         This flag tells the command not to reuse existing deltas
 145         but compute them from scratch.
 146
 147 --no-reuse-object::
 148         This flag tells the command not to reuse existing object data at all,
 149         including non deltified object, forcing recompression of everything.
 150         This implies --no-reuse-delta. Useful only in the obscure case where
 151         wholesale enforcement of a different compression level on the
 152         packed data is desired.
 153
 154 --compression=[N]::
 155         Specifies compression level for newly-compressed data in the
 156         generated pack.  If not specified,  pack compression level is
 157         determined first by pack.compression,  then by core.compression,
 158         and defaults to -1,  the zlib default,  if neither is set.
 159         Add \--no-reuse-object if you want to force a uniform compression
 160         level on all data no matter the source.
 161
 162 --delta-base-offset::
 163         A packed archive can express base object of a delta as
 164         either 20-byte object name or as an offset in the
 165         stream, but older version of git does not understand the
 166         latter.  By default, git-pack-objects only uses the
 167         former format for better compatibility.  This option
 168         allows the command to use the latter format for
 169         compactness.  Depending on the average delta chain
 170         length, this option typically shrinks the resulting
 171         packfile by 3-5 per-cent.
 172
 173 --threads=<n>::
 174         Specifies the number of threads to spawn when searching for best
 175         delta matches.  This requires that pack-objects be compiled with
 176         pthreads otherwise this option is ignored with a warning.
 177         This is meant to reduce packing time on multiprocessor machines.
 178         The required amount of memory for the delta search window is
 179         however multiplied by the number of threads.
 180         Specifying 0 will cause git to auto-detect the number of CPU's
 181         and set the number of threads accordingly.
 182
 183 --index-version=<version>[,<offset>]::
 184         This is intended to be used by the test suite only. It allows
 185         to force the version for the generated pack index, and to force
 186         64-bit index entries on objects located above the given offset.
 187
 188
 189 Author
 190 ------
 191 Written by Linus Torvalds <torvalds@osdl.org>
 192
 193 Documentation
 194 -------------
 195 Documentation by Junio C Hamano
 196
 197 See Also
 198 --------
 199 linkgit:git-rev-list[1]
 200 linkgit:git-repack[1]
 201 linkgit:git-prune-packed[1]
 202
 203 GIT
 204 ---
 205 Part of the linkgit:git[7] suite